Unix Socket Programming Question:
After the chroot(), calls to socket() are failing. Why?
Answer:
On systems where sockets are implemented on top of Streams (e.g. all SysV-based systems, presumably including Solaris), the socket() function will actually be opening certain special files in /dev. You will need to create a /dev directory under your fake root and populate it with the required device nodes (only).
Your system documentation may or may not specify exactly which device nodes are required; suggested checking the man page for ftpd, which should list the files you need to copy and devices you need to create in the chroot'd environment.)
A less-obvious issue with chroot() is if you call syslog(), as many daemons do; syslog() opens (depending on the system) either a UDP socket, a FIFO or a Unix-domain socket. So if you use it after a chroot() call, make sure that you call openlog() *before* the chroot.
Your system documentation may or may not specify exactly which device nodes are required; suggested checking the man page for ftpd, which should list the files you need to copy and devices you need to create in the chroot'd environment.)
A less-obvious issue with chroot() is if you call syslog(), as many daemons do; syslog() opens (depending on the system) either a UDP socket, a FIFO or a Unix-domain socket. So if you use it after a chroot() call, make sure that you call openlog() *before* the chroot.
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